1980 Prize Paper Digital Impulse Recorder for High-Voltage Laboratories

A digital recorder has been developed for use in HV laboratories as a prospective replacement for conventional impulse oscilloscopes. The new apparatus has a sufficiently high time resolution to record the fastest microsecond impulses used for HV testing and also allows slower switching transients to be monitored. In order to immunize the sensitive electronic circuits of the recorder against the high electromagnetic interference of HV test areas, the authors conducted an experimental study of the nature of this interference and its magnitude and used the results to calculate the shielding and supply-line conditioning systems. The recorder is designed as a mobile unit composed of an input attenuator compatible with the impulse voltage dividers, an analog-to-digital converter Biomation 8100, an interface and a graphic computer terminal Tektronix 4051. The recorded impulses are displayed with the calibrated voltage and time axes on the terminal screen and can be printed or stored on magnetic tape for further processing. Specialized programs could be applied to simplify the processing of results of impulse tests on HV insulators, air gaps and power transformers. The paper points out new problems ensuing from the application of digital recorders to the HV impulse testing technique.